Nanolaser is small as speck of dust

Creating a tiny version of a coaxial cable, researchers at the University of California at San Diego create smallest laser to date, an advance that could lead to optical computer chips or high-resolution displays.

Nanolaser study co-author Mercedeh Khajavikhan in optics laboratory.
University of California San Diego Jacobs School of Engineering

Researchers have created the smallest room-temperature laser, a breakthrough that could lead to faster optical computers.

A group at the University of California at San Diego published a paper in Nature today that describes a new method for making lasers smaller than ever before. The technique allows for low-power lasers smaller than one micron in diameter. A human hair is about 600 microns wide and air-borne particles such as pollen are as small as 10 microns.

A tiny coaxial cable to produce a low-power laser resonator. The laser light is emitted through a hole.
Mercedeh Khajavikhan and Aleksandar Simic

The challenge with making very small lasers has been the amount of power required to generate a sustained beam of light. To get around this "threshold" energy level, the UCSD team created a laser with a similar structure to a coaxial cable.

This tiny coaxial cable, or "nanocavity," is a metal rod encased by a semiconductor material. The construction avoids the electromagnetic effects normally caused by at this scale, allowing for smaller laser resonators. The lasers can be comparable in size the wavelengths of light they produce, according to the researchers.

The lasers built for their experiments aren't going to show up in DVD players or computers any time soon. The researchers are still exploring the theory behind laser construction at this scale and seeking out potential applications.

About the author

Martin LaMonica is a senior writer covering green tech and cutting-edge technologies. He joined CNET in 2002 to cover enterprise IT and Web development and was previously executive editor of IT publication InfoWorld.
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